Current antenna technology results in fixed-length, or finite and manual-adjustment, antennas that are at least one quarter of a wavelength in length or antennas that include an electrical load. Using current technology, an antenna may range in length from inches for a super high frequency antenna to miles for an extremely low frequency antenna. A large antenna presents logistic problems and requires more power to operate than does a small antenna. Tactical and mobile communication systems require antennas that have high gain, are small, are lightweight, and use little electrical power.
In two articles, the first by Nathan Cohen and the second by Nathan Cohen and Robert G. Hohlfeld, entitled "Fractal Antennas Part 1," published in the summer of 1995 by Communications Quarterly on pages 7-22, and "Fractal Loops and the Small Loop Approximation," published in the winter of 1996 by Communications Quarterly on pages 77-81, the use of fractals in the design of antennas is described. A fractal is a pattern that includes a certain pattern replicated a number of times at different sizes so that the fractal has the same pattern as the certain pattern replicated therein. Typically, antenna designers use classic Euclidean geometry (e.g., simple squares and triangles) to design the shape of an antenna to obtain certain antenna characteristics. A fractal pattern with its more intricate shape and finer resolution (e.g., snowflake pattern) provides greater options and control to the antenna designer to obtain certain antenna characteristics. Antennas designed by the method disclosed in these articles are not re-programmable (i.e., reconfigurable) as is the antenna of the present invention.
U.S. Pat. No. 5,719,794, entitled "PROCESS FOR THE DESIGN OF ANTENNAS USING GENETIC ALGORITHMS," discloses a method of having a computer design an antenna to a user-definable specification by having the computer select user-definable design options, testing the particular antenna resulting from the selection, and refining the design using additional selections until the resulting antenna meets the specification defined by the user. Antennas is using the method of U.S. Pat. No. 5,719,794 are not re-programmable (i.e., reconfigurable) as is the present invention. U.S. Pat. No. 5,719,794 is hereby incorporated by reference into the specification of the present invention.
The problem with fixed-length, or finite and manual-adjustment, antennas is that they may not meet the desired characteristics, be too large, be too heavy, and consume too much electrical power. Fixed antennas that employ fractal patterns provide a greater chance of meeting a particular characteristic, but may not be adjustable to allow either fine-tuning of the antenna or completely changing the characteristics of the antenna. The present invention is a solution to the problems associated with the above-identified antennas.